After giving precious few details when they announced the title back in September, MTV’s Harmonix games studio and The Beatles’ *Apple* Corps have opened BeatlesRockBand.com to offer a preorder sign-up for the upcoming game based on the band — and, as the name suggests, turns out it’s a Rock Band spinoff after all.

The Beatles: Rock Band, which the companies earlier said would be ready by this coming Christmas, will in fact by released worldwide on Sept. 9, across Xbox 360, Playstation 3 and Nintendo Wii. Though Harmonix in December told reporters the title would not be a Rock Band expansion pack but “a new full-blown custom game title production built from the ground up,” the game will, in fact, be tied in to the franchise. The name sure is a giveaway — though, unlike Rock Band‘sGuitar Hero‘s Aerosmith and Metallica expansion packs, this time “The Beatles” comes first — but the game can also be played with existing Rock Band instruments. “Other current music-based video-game peripherals” can also be used, though it’s not clear whether this includes those for Activision (NSDQ: ATVI) Blizzard’s rival Guitar Hero franchise.

The game will sell for $59.99 but the Beatles guitar controllers specific to the game will come separately for $99.99 (not clear whether that’s each). A limited edition premium bundle, featuring controllers modeled after instruments played by the band, will sell for a hefty $249.99. With add-on pricing like that, the game could turn out to be, as all concerned had hoped, one of the most lucrative in history.

MTV Games will publish the game, EA will be a distribution partner. As an enticement to preorder, “exclusive” new content created by those involved will be given in the next few months to those who sign up. As already stated, it’s a music game, allowing multiple players to pick up guitar, bass, drums and microphone controllers to play along with the Fab Four’s catalog on a musical “journey”. Agreements have been struck between EMI, publisher Sony/ATV, *Apple* Corps and MTV for the game, which has the blessing of Paul McCartney, Ringo Starr, Olivia Harrison and Yoko Ono. In a neat link to the past, Giles Martin, the Grammy-winning son of Beatles producer Sir George Martin, has been tapped to produce the game